Compaction machines are used to compact landfill sites, garbage dumps and other such locations. These machines typically include a self-propelled vehicle having three or four large wheels made of steel. Each wheel has a hub mounted to one end of an axle and a rim disposed around and radially out from the hub. The rim typically includes an outer wrapper defining the width of the wheel. A plurality of cleats are usually mounted on the outer wrapper. In the past, to achieve the highest density possible for the refuse being compacted, compactor wheels having different widths have been used.
Relatively narrow compactor wheels have been used to produce greater compacting pressures (i.e., PLI or pounds per linear inch) and, thereby, higher refuse densities. Being able to achieve higher refuse densities extends the life of the landfill site, garbage dump or other such location. Such narrow compactor wheels are typically used to compact relatively high density refuse (e.g., clay, foundry sand, etc.). Such narrow compactor wheels have been too narrow to support the weight of the compaction machine as it travels over refuse that is loose or has too low of a density (e.g., plastic bags, paper products, food waste, etc.). As a result, if they are too narrow, the narrow compactor wheels can get bogged down in such loose or low density refuse causing the compaction machine to work less efficiently and to get stuck continuously.
In order to ensure the highest degree of compaction and to help avoid getting compaction machines stuck in the refuse, a landfill operator is often forced to purchase two sets of compactor wheels for each compaction machine. The same compaction machine is then used to compact both low and high density refuse. One set of wide wheels is used to compact the loose and low density refuse until the refuse reaches a density capable of supporting the narrow wheels. Then, the set of narrow wheels is used to compact higher density refuse.
One problem with this arrangement is that the landfill operator has to incur the additional cost of an extra set of compactor wheels. In addition, there are significant maintenance costs associated with the wheels of a compaction machine. Removing the compactor wheels is a labor intensive and time consuming process. Compactor wheels can have an outside diameter of up to 84 inches and weigh up to five tons per wheel. It can take up to two working days or more to remove and replace the wheels of a typical compaction machine. Such down time can also result in lost income from refuse left uncompacted. In addition, most landfill sites do not have backup compaction machines available to take over during the down times. The operator of a landfill can risk being charged federal and state fines for each day the trash at the site remains uncompacted.
Accordingly, there is a need for a way to eliminate having to keep a set of narrow and a set of wide compactor wheels for each compaction machine in order to compact both low density and high density refuse.